Lock-down square-butt shingle



y 1959 H. A'BRAHAM LOCK-DOWN SQUARE-BUTT SHINGLE Filed Jan. 25, 1956 I N VEN TOR. HERBERT ABRAHAM BYQL ATTORNEY United States Patent LOCK-DOWN SQUARE-BUTT SHINGLE Herbert Abraham, New York, N.Y., assignor to The Ruberoid Co., New York, N.Y., a corporation of New Jersey Application January 25, 1956, Serial No. 561,286

3 Claims. (Cl. 108-7) This invention relates to improvements in lock-down shingles of the type that when laid have the appearance of square-butt shingles. Examples of such shingles are shown in my Patents Nos. 2,659,322 and 2,452,708.

Shingles of that type have their exposed butt portions separated by vertical slots or cut-outs, and have a look ing tab extending downward from the butt or lower straight edge of each exposed portion. Horizontal locking slots are located in the shingles in line with the upper edge of the vertical slots. When the shingles are laid, the locking tabs of the shingles of each upper course are engaged in the locking slots of the shingles of the underlying course so as to lock down the butts. The shingles are cut with a plurality of exposed or butt portions, but for ease in handling and application each shingle preferably has only two such portions.

It has been found in practice that with the shingles of this type now in use infiltration of water through the locking slots sometimes occurs during severe Windstornis accompanied by heavy rain. Because of this there is some danger that rain infiltrating into the locking slot of an upper shingle may, by reason of the force of the wind or other cause, be blown or enter under that shingle and seep through the joint between two underlying shingles or over the upper edge of the underlying shingles.

The principal object of the invention is to provide a lock-down square-butt shingle of novel form that obviates any likelihood of seepage of water through the joints or over the upper edge of underlying shingles by reason of rain passing or trickling through the locking slot of an overlying shingle due to high winds and other causes. The shingle of my invention afiords an increased factor of safety against such mishapwithout any substantial increase in the amount of material required to cover a square of roof area.

Another object of the invention is to provide a shingle of the character described of such form as to facilitate proper application of the shingles on a roof in horizontal courses and with the locking tabs of each succeeding course properly engaged in the locking slots of the shingles of the underlying course. The form of the present shingle is such that all of the shingles of any course will be in self-alignment after the first shingle of the course is properly applied and nailed, and that the shingles of each succeeding course will be located that their locking tabs will engage properly in the locking slots of the underlying course. With the prior art shingles there is a possibility, through faulty application, that some of those in any course may be applied slightly out of alignment with others in the same course. Any such irregularity of application will result in an unsightly appearance due to the fact that some of the locking tabs may not be fully inserted in their locking slots, thus leaving a part of the tab exposed above the lower edge of the locking slot. The form of the present shingle also provides visual indications to show that the locking tabs 2,884,878 Patented May 5, 1958 are fully engaged in the locking slots, and so further facilitates proper application of the shingles.

In the accompanying drawings:

Fig. 1 is a plan view of a preferred form of lock-down square-butt shingle embodying the invention; and

Fig. 2 is a plan view of a portion of a covering formed by the shingles as applied in courses to a roof.

The shingles are cut from sheets or webs of asphalt roofing material and the like. Each shingle comprises a body portion 10 formed with two similar square-butt portions 11 that constitute the exposed portions when the shingles are laid. Each butt portion has a straight lower or butt edge 12, and the two portions 11 are separated by a vertical slot 13.

Extending downward from the lower edge of each butt portion is a locking tab 14. At or adjacent the upper end of the vertical slot 13 is a horizontal locking slot 15. A similar horizontal slot 15' is cut into one side edge of the shingle. The opposite side edge is indented at 16 so that when the shingles are laid side by side in courses, as shown in Fig. 2, a vertical slot 13' similar to the vertical slot 13, will be formed between each two adjacent shingles.

The features of construction described in the foregoing two paragraphs are shown in my prior patents, and are not claimed as novel features in the present invention.

According to the present invention, the body 10 of the shingle is formed with a shoulder 17 that projects outward therefrom along one side, in this instance the left side. The shoulder serves two important purposes. Firstly, as shown in Fig. 2, it serves to locate the joint A between any pair of adjacent underlying shingles, as BB, a substantial distance away from the left end of the locking slot 15 of shingle C of the overlying course, and so prevents, or materially reduces, any likelihood that rainwater which may infiltrate the slot 15' will trickle down and seep through the joint A. Secondly, the shoulder serves as a means of aligmnent of the shingles in horizontal courses.

The shoulder is defined by an outwardly inclined edge 18, and a vertical edge 19 that, in the present instance, extends up to the portion 20 of the upper edge of the shingle. The opposite or right side of the shingle has an inclined edge 21 and a vertical edge 22 that are complementary in direction and length to the edges 18 and 19, respectively. The vertical edge 19 terminates at its upper end in an upper edge portion 23. The meeting points of edges 18 -19 and 21--22 form corners 24 that serve to align the overlying shingles with the underlying ones, as will be hereinafter explained, to effect the de sired amount of headlap and to provide visual indications that the locking tabs of the shingles of an upper course are properly and fully inserted in the locking slots of the shingles of the next under course.

The upper edge of each shingle has two like projections 25 each having a horizontal top edge 26. The two projections are separated by an intervening horizontal edge 27 and a space of the same shape and size as either projection. The edge 27 is equal in length to that of either edge 26, as well as to the combined lengths of the edges 26 and 23. This arrangement provides the shingle with a serrated upper edge of symmetrical shape and thus permits of cutting two rows, or multiples of two rows, from a sheet or web of material with the shingles in the pairs of rows in mutually reversed position, and without any waste of material in shaping the upper edges of the shingles of the two rows.

The projections 25 are so located along the upper edge that when the shingles are laid in overlapping courses, as in Fig. 2, the projections of each shingle of an underlying course, as for example the course that includes shingles B and B, will lie under and extend a substantial distance beyond the locking slots 15 of the overlying course of shingles, exemplified by shingles C and C'( Shingles of this form and arrangement have an increased headlap. This provides an enhanced factor of safety against leakage, over the upper edge of the underlying shingles, by water that may enter through the locking slots of the overlying shingles and be blown up over said upper edge.

In applying the shingles in overlapping horizontal courses, the shingles of each course will be automatically laid in self-alignment by reason of the mating of the edges 18 19 with the edges 2122 of the preceding shingle of the course. The shingles of each succeeding overlying course will be laid with their locking tabs fully engaged in the locking slots of the underlying shingles by registering the corners 24 of the overlying shingles C-C' on the edges 26 of the projections of the underlying shingles BB'.

Each shingle is fastened by three nails, one of which is driven into the shingle above and slightly to the right of the indentation 16 and the other two above and slightly to the left of the ends of the locking slots 15-15. The three nails are in line with one another, and in position to be covered by the butts of the overlying shingles, as seen in Fig. 2.

For the purpose of description, but not of limitation, each shingle, in its preferred form, has the following dimensions: overall height, measured from the lower edge 12 to the upper edge'portion '26 of either projection is 18%; the overall width between the edges 19 and 22 is 25"; the width of the shoulder 17 is 2 /2"; the width of the vertical slot 13 is /2", as is conventional in the square-butt shingle; and the height of each of the inclined edges 18 and 21, measured vertically, is 2%". The height of each projection is 3".

When laid, each shingle has a vertical exposure of 7 /5" and a head-lap of 3 /2", the head-lap being measured from the upper edge of the locking slot. With shingles of the form of this invention, having these dimensions, it requires only 75 shinges to cover per square, and a gross area per square of approximately 244 square feet of shingle material. Furthermore, two rows of shingles of the stated form and dimensions may be cut from a sheet or web of roofing material of 37%" width.

- Iclaim:

1. A shingle of the lock-down square-butt type comprising a body of flexible roofing material having a pair of similar square-butts at its lower portion which butt portions are separated midway between their widths by a vertical slot that terminates at its upper end in a locking slot, a locking tab at the lower end of each square-butt portion, a shoulder extending outwardly from one side of the upper portion of the body and a complementary indentation in the opposite side, the width of said shoulder being substantially one-tenth of the overall width of the shingle, said shoulder providing a factor of safety against leakage through the joint of two adjacent underlying shingles of water that might enter through the locking slot of an overlying shingle when the shingles are applied in overlapping courses with the locking tabs of the shingles of each upper course engaged in the locking slots of the shingles of the next lower course.

2. A shingle as in claim 1 wherein the upper edge of the shingle has a plurality of like projections each having a straight top edge, the projections being separated by a horizontal edge portion of the same length as the top edge of a projection and an intervening space of the same size and shape in reverse of a projection, said projections being located on the upper edge of the shingle in position that when the shingle is laid in overlapping courses with like shingles, the projections of the underlying shingles will lie under and extend up beyond the locking slots of the overlying shingles to provide a factor of safety against leakage over the upper edge of the underlying shingles by water that may enter through the slots of the overlying shingles and be blown by wind up over the upper edge of the underlying shingles.

3. A shingle as in claim 1 wherein the upper edge has a plurality of projections, and wherein the edges of the shoulder and the indentation each comprise like intersecting portions the meeting points of which form corners, which corners, when the shingle is laid is overlapping courses with like shingles, by being applied in registration on and with the top of projections of the shingles of the immediately underlying course, provide visual indication that the locking tabs of the overlying shingle are inserted down to their full extent in the locking slots of said underlying shingles in which they are engaged.

References Cited in the file of this patent UNITED STATES PATENTS 1,425,991 Lesher Aug. 15, 1922 1,447,567 Overbury Mar. 6, 1923 2,144,678 Goldschmidt Jan. 24, 1939 2,655,879 Lee Oct. 20, 1953 2,659,322 Abraham Nov. 17, 1953 

